J. Zhou

Southeast University (China), Nan-ching-hsü, Jiangxi Sheng, China

Are you J. Zhou?

Claim your profile

Publications (2)4.55 Total impact

  • C L Chu · CY Chung · J Zhou · YP Pu · P H Lin
    [Show abstract] [Hide abstract]
    ABSTRACT: A bioactive sodium titanate/titania graded film was formed in situ on NiTi shape memory alloy (SMA) by oxidizing in H(2)O(2) solution and subsequent NaOH treatment and characterized by scanning electron microscopy, Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy (XPS). The bioactivity of the film was investigated using a simulated body fluid (SBF) soaking test. A titania (TiO(2)) layer was first found on NiTi substrate after oxidized in H(2)O(2) solution, and then a porous sodium titanate (Na(2)TiO(3))/titania film with many Ti--OH groups and a trace of Ni(2)O(3) was formed by the reaction of partial TiO(2) phase with NaOH solution. After immersion in SBF for 12 h, apatite was observed to nucleate and grow on the film. With longer soaking time, more apatite appeared on its surface but our control experiments didn't reveal any apatite formation on the chemically polished NiTi SMA, which indicates the bioactivity of NiTi implants could be improved by the formation of the bioactive film. Moreover, XPS depth profiles of O, Ni, Ti, and Na show the bioactive film possesses a smooth graded interface structure to NiTi substrate, which is in favor of sufficient mechanical stability of apatite layer by subsequent deposition in SBF.
    No preview · Article · Dec 2005 · Journal of Biomedical Materials Research Part A
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chemically polished NiTi shape memory alloy (SMA) substrate was treated with a boiling aqueous solution containing hydrogen peroxide to form titania film in situ at low temperature. The surface characterizations of titania film on NiTi substrate were investigated by scanning electron microscopy, X-ray diffractometry and X-ray photoelectron spectroscopy. The results show that titania film is successfully fabricated in situ on NiTi SMA by this surface oxidation method. It is mainly composed of rutile and anatase, whose surface compositions and morphologies are sensitive to H2O2 content. In situ formation mechanism of titania film on NiTi substrate was discussed based on the experimental results.
    No preview · Article · Aug 2005 · Transactions of Nonferrous Metals Society of China